Once the doc has chopped your bollocks off, there’s really no “reversal”.
There is actually a form of M2F surgery that is fully reversible.
It can work for most but not for all.
The testes are relocated internally...this is simple.
The penis is placed internally leaving just the sensitive part at the surface to serve as clitoris.
The urethra is relocated lower on the perineum.
The scrotal tissue is used to create labia.
A vagina is formed using a short piece of small intestine and is self lubricating.
The entire affair can be reversed.
Hormonal treatment will stop the testis from producing testosterone.
A somewhat more involved procedure but the reversibility would be worth the trouble in some cases. The most difficult part is relocation of the penis below the surface.
—Obviously does not work well if the patient has a very large penis.